Urine metabolomics profiling has potential for non-invasive RCC staging, in addition to providing metabolic insights into disease progression. In this study, we utilized liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR), and machine learning (ML) for the discovery of urine metabolites associated with RCC progression. Two machine learning questions were posed in the study: Binary classification into early RCC (stage I and II) and advanced RCC stages (stage III and IV), and RCC tumor size estimation through regression analysis. A total of 82 RCC patients with known tumor size and metabolomic measurements were used for the regression task, and 70 RCC patients with complete tumor-nodes-metastasis (TNM) staging information were used for the classification tasks under ten-fold cross-validation conditions. A voting ensemble regression model consisting of elastic net, ridge, and support vector regressor predicted RCC tumor size with a R2 value of 0.58. A voting classifier model consisting of random forest, support vector machines, logistic regression, and adaptive boosting yielded an AUC of 0.96 and an accuracy of 87%. Some identified metabolites associated with renal cell carcinoma progression included 4-guanidinobutanoic acid, 7-aminomethyl-7-carbaguanine, 3-hydroxyanthranilic acid, lysyl-glycine, glycine, citrate, and pyruvate. Overall, we identified a urine metabolic phenotype associated with renal cell carcinoma stage, exploring the promise of a urine-based metabolomic assay for staging this disease.
12 March 2014 in BMC Complementary and Alternative Medicine
Snail transcription factor can induce epithelial-mesenchymal transition (EMT), associated with decreased cell adhesion-associated molecules like E-cadherin, increased mesenchymal markers like vimentin, leading to increased motility, invasion and metastasis. Muscadine grape skin extract (MSKE) has been shown to inhibit prostate cancer cell growth and induce apoptosis without affecting normal prostate epithelial cells. We investigated novel molecular mechanisms by which Snail promotes EMT in prostate cancer cells via Reactive Oxygen Species (ROS) and whether it can be antagonized by MSKE.
Background (−)-Solenopsin A is a piperidine alkaloid that is a component of the venom of the fire antSolenopsis invicta. Previously, we have demonstrated that solenopsin exhibit anti-angiogenic activity and downregulate phosphoinositol-3 kinase (PI3K) in the p53 deficient renal cell carcinoma cell line 786-O. Solenopsin has structural similarities to ceramide, a major endogenous regulator of cell signaling and cancer therapy induced apoptosis. Methods Different analogs of solenopsin were synthesized in order to explore structure-activity relationships. The anti-proliferative effect of solenopsin and analogs was tested on six different cell lines, including three tumor cell lines, two normal cutaneous cell lines, and one immortalized hyperproliferative cell line. FRET-based reporters were used to study the affect of solenopsin and analogs on Akt activity and PDK1 activation and sucrose density gradient fractionation was performed to examine recruitment of PTEN to membrane rafts. Western-blotting was used to evaluate the affect of solenopsin and analogs on the Akt and the MAPK 44/42 pathways in three different tumor cell lines. Measurement of cellular oxygen consumption rate together with autophagy staining was performed to study mitochondrial function. Finally, the affect of solenopsin and analogs on ROS production was investigated. Results In this paper we demonstrate that solenopsin analogs with potent anti-proliferative effects can be synthesized from inexpensive dimethylpyridines. To determine whether solenopsin and analogs act as ceramide analogs, we examined the effect of solenopsin and analogs on two stereotypic sites of ceramide activity, namely at lipid rafts and mitochondria. We found that native solenopsin, (−)-solenopsin A, inhibits functional Akt activity and PDK1 activation in lipid rafts in a similar fashion as ceramide. Bothcisandtransanalogs of solenopsin reduce mitochondrial oxygen consumption, increase reactive oxygen, and kill tumor cells with elevated levels of Akt phosphorylation. However, only solenopsin induces mitophagy, like ceramide. Conclusions The requirements for ceramide induced mitophagy and inhibition of Akt activity and PDK1 activation in lipid rafts are under strict stereochemical control. The naturally occurring (−)-solenopsin A mimic some of the functions of ceramide and may be therapeutically useful in the treatment of hyperproliferative and malignant disorders of the skin, even in the presence of elevated levels of Akt.
In our previous study, we observed that androgen deprivation therapy (ADT) may induce a compensatory increase in MAPK or JNK signaling. Here, we tested the effects of the MEK inhibitors PD0325901 and GSK1120212, ERK1/2 inhibitor GDC-0994, and the JNK inhibitor AS602801 alone and in combination with the AR inhibitor enzalutamide (ENZ) in androgen-sensitive LNCaP cells and androgen-resistant C4-2 and 22Rv1 cells. Enzalutamide combined with AS602801 synergistically killed LNCaP, C4-2, and 22Rv1 cells, and decreased migration and invasion of LNCaP and C4-2 cells. We studied the combination of enzalutamide with AS602801 in vivo using luciferase labeled LNCaP xenografts, and observed that combination of ENZ with AS602801 significantly suppressed tumor growth compared with either drug alone. Importantly, combination therapy resulted in dramatic loss of AR mRNA and protein. Surprisingly, mechanistic studies and Nanostring data suggest that AS602801 likely activates JNK signaling to induce apoptosis. Since AS602801 had sufficient safety and toxicity profile to advance from Phase I to Phase II in clinical trials, repurposing of this compound may represent an opportunity for rapid translation for clinical therapy of CRPC patients.
Dysfunctions in epigenetic regulation play critical roles in tumor development and progression. Histone deacetylases (HDACs) and histone acetyl transferase (HAT) are functionally opposing epigenetic regulators, which control the expression status of tumor suppressor genes. Upregulation of HDAC activities, which results in silencing of tumor suppressor genes and uncontrolled proliferation, predominates in malignant tumors. Inhibition of the deacetylase activity of HDACs is a clinically validated cancer therapy strategy. However, current HDAC inhibitors (HDACi) have elicited limited therapeutic benefit against solid tumors. Here, we disclosed a class of HDACi that are selective for sub-class I HDACs and preferentially accumulate within the normal liver tissue and orthotopically implanted liver tumors. We observed that these compounds possess exquisite on-target effects evidenced by their induction of dose-dependent histone H4 hyperacetylation without perturbation of tubulin acetylation status and G0/G1 cell cycle arrest. Representative compounds 2 and 3a are relatively non-toxic to mice and robustly suppressed tumor growths in an orthotopic model of HCC as standalone agents. Collectively, our results suggest that these compounds may have therapeutic advantage against HCC relative to the current systemic HDACi. This prospect merits further comprehensive preclinical investigations.